This will be the first of two trials for Manafort this year. A trial on federal charges in Washington, DC, is scheduled to begin in September.

Manafort is charged in Washington with making false statements about his foreign lobbying work, which he primarily did for Ukrainian politicians, and engaging in a money laundering conspiracy.

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His 18 criminal charges in Virginia federal court -- which total more than the five he faces in Washington and carry a much heavier potential prison sentence -- accuse him of bank fraud and lying on income tax returns and regarding his foreign bank accounts.

He has denied all charges in both courts.

In the DC charges alone, Manafort faces a likely sentence of more than 15 years to almost 20 years in prison if found guilty. He faces a maximum of 305 years in prison if found guilty on all charges in Virginia.

Manafort was first indicted last fall alongside Trump campaign deputy and longtime business partner Rick Gates, who in February changed his plea and agreed to cooperate with the office of special counsel Robert Mueller.

If Manafort were to choose to avoid a trial and change his plea to guilty, he could be forced to share details he knows about Trump campaign officials' contact with Russians and other foreign nationals. Manafort for decades had conducted business built upon his relationships with Russian-sympathetic Ukrainians and other powerful European former politicians, and had been in contact with them while leading the Trump campaign. He was among the Trump campaign officials in the meeting at Trump Tower in June 2016 when a Russian lawyer discussed sanctions, for instance.